esp32_4buttons_4leds.ino

#define EXTERNAL_BUTTON_B1 27
#define EXTERNAL_BUTTON_B2 19 /* B2 <-> B3) */
#define EXTERNAL_BUTTON_B3 18 /* B2 <-> B3) */
#define EXTERNAL_BUTTON_B4 23

#define R1_3  32
#define R2_3  33
#define R3_3  25
#define R4_3  26

void setup() {
    pinMode(EXTERNAL_BUTTON_B1, INPUT_PULLUP);
    pinMode(EXTERNAL_BUTTON_B2, INPUT_PULLUP);
    pinMode(EXTERNAL_BUTTON_B3, INPUT_PULLUP);
    pinMode(EXTERNAL_BUTTON_B4, INPUT_PULLUP);

    pinMode(R1_3, OUTPUT);
    pinMode(R2_3, OUTPUT);
    pinMode(R3_3, OUTPUT);
    pinMode(R4_3, OUTPUT);
}

void loop() {
  digitalWrite(R1_3,!digitalRead(EXTERNAL_BUTTON_B1));
  digitalWrite(R2_3,!digitalRead(EXTERNAL_BUTTON_B2));
  digitalWrite(R3_3,!digitalRead(EXTERNAL_BUTTON_B3));
  digitalWrite(R4_3,!digitalRead(EXTERNAL_BUTTON_B4));
}